Hybrid electric and electric vehicles include a battery pack to supplement or support the vehicle powertrain during operation. The battery pack generally requires cooling. Cooling systems can include a fan to direct air away from the battery cells and/or modules in the battery pack. Battery pack support devices, e.g., a charger, generator, convertor or other device may require cooling as well. In the past, a separate fan has been dedicated to the battery support device. Two fans serve different functions: the first, to cool the high voltage battery pack when the vehicle is in driving mode; and the second, to cool a charger when the vehicle is in park and/or being charged. Each fan requires additional costs for parts, assembly, packaging, warranty and failure mode management. Accordingly, it is desirable to have a single fan cooling system that cools both the battery pack and any battery support device.
U.S. Pat. No. 6,094,927 titled “Cooling Structure and Electric Vehicle” regards a secondary air passage positioned underneath battery cells, which has a smaller cross-section than the primary passage in order to increase flow to an electric part. Individualized air flow management is not provided, however, where the cooling system can separately control flow between to battery modules and the electric part.
Therefore, it is desirable to have a cooling system for a vehicle battery pack that supports independent cooling of the battery module(s) and battery support devices but with the use of a single fan.